Saïf al-Islam Gaddafi, the son of former Libyan leader Moamer Kadhafi, was shot dead at his home in western Libya on Tuesday, several sources have confirmed to RFI.
Libyan television channel Libya al-Ahrar said people close to Saïf al-Islam had also confirmed his death without revealing the circumstances.
His adviser and representative to the national dialogue committee, Abdullah Othman Abdurrahim, also announced the passing of the 53-year-old in a Facebook post, without further details.
Media reports said Saïf al-Islam was killed south of the city of Zintan, in western Libya. He was alone at home when four armed men broke into the residence and opened fire.
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Libya al-Ahrar said the attackers disabled surveillance cameras before storming the house and killing him, citing comments by Abdullah Othman Abdurrahim.
Saïf al-Islam's lawyer later confirmed to the French news agency AFP that "a commando of four people" had killed him at his home.
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First reactions
His cousin, Hamid Kadhafi, described the killing as a martyrdom. "Doctor Saïf al-Islam fell as a martyr," he told Libya al-Ahrar by telephone.
Saïf al-Islam's lawyer, Abdallah Zaydi, condemned what he called a "cowardly assassination" and an "odious crime that adds to the series of crimes committed against the Libyan people".
Photos circulating on social media showed Saïf al-Islam's body lying in the back of a vehicle.
His political adviser said the body had been taken to a private hospital in Zintan and that four judges had arrived in the city to open an investigation.
"He will not be buried before the end of the investigation," the adviser said.
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Denials and past charges
Some sources accused Brigade 444, an armed group led by Mahmoud Hamza, of carrying out the assassination.
The brigade denied any involvement. "We affirm that no force is deployed in Zintan and we deny the existence of any decision to pursue Saïf al-Islam Kadhafi," the group said in a statement.
Long seen as a potential successor to his father, Saïf al-Islam was wanted by the International Criminal Court for crimes against humanity.
He was arrested in 2011, sentenced to death in 2015 and later released under an amnesty.
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